Metal rectifier



NW; 3@, 19%. A, M, SEARLE 2,454,843

METAL RECTIFIER I Filed Jan. 14, 1944 2 Sheets-Sheet 1 FIG. F762. 2

A. M. SEARLE Nov. 30, 19348.

. METAL RECTIFIER Filed Jan. 14, 1944 2 Sheets-Sheet 2 Patented Nov. 30, 1948 METAL nac'rndan Arthur Mackenzie Searle, London, England. al-

signor,- by mesne assignments, to International Standard Electric Corporation, New a corporation of Delaware York, N. Y..

Application January 14, 1944, Serial No. 518.239

In Great Britain February 4, 1943 This invention relates to dry contact metal rectifiers. Such rectifiers are usually made in disc form, either circular or rectangular in shape and are provided with holes by means of which they are threaded on to a rod with the necessary insulators, washers and contact arms to form rectifier assemblies. In the event of a rectifier proving unsatisfactory after such assembly it is necessary to unthread rectifiers, insulators, washers and contact arms in order to remove'the faulty rectifier and after replacing it by another to rethread the elements in the correct order.

According to the present invention a rectifier is provided with a slot in its periphery adapted to fit over an assembly rod, and the hole is omitted.

By this means rec'tifiers may be readily as- I sembled ona rod or rods without threadin and a faulty rectifier may .be removed from the assembly without needing to unthread any of the elements.

The invention will be better understood from the following description taken in conjunction with the accompanying drawings,

' Fig. 1 is a face view of a rectifier disc provided with opposed slots;

" Figs. 2 and 3 are similar views of modified forms;

I Fig.- 4 is a side elevation sembly;

Fig. 5 is a diagram of the electrical connections of the Fig. 4 assembly;

Fig. 6 is a rectifying circuit employing the Fig. 4 assembly, and

Fig. 7 is, a face view of a rectifier disc showing a further modification.

of a rectifier disc as- Referring to the drawings Figs. 1 and 2 show circular rectifier discs i each provided with a slot 2 according to the invention. In Fig. 1 the slot 2 is Just deep enough to take the full diameter of the assembly rod and permit sufilcient outward movement of the disc to free the opposite edge thereof. Preferably, however, the slot 2 is made deep enough so that a separating washer on the rod passing through slot 2, may lie wholly against the rectifier disc i without protruding. In the case of a circular disc, it is preferable to make the slot 2, as shown in Fig. 2, deep enough to extend to the centre of the disc. Rectifier discs with slots as shown in Fig. 1 or 2 may be assembled on a rod and to remove one of the discs, it is only necessary to slacken the clamping nuts, slide oil the faulty rectifier, replace it with a fresh one and retighten the clamping nuts.

moved away from this second rod into a position from which it can be removed from the rod in slot 2 without unthreading an assembly mounted on this last mentioned rod.

The slot or slots in a rectifier disc may be provided at any stage of its manufacture. Thus, they may be made in the base plate before the semi-conductor rectifying material is formed thereon or applied thereto, or in the case in which a plurality of discs are to be cut or punched from a larger rectifier sheet, the slots may be cut or punched when the discs are removed from the larger sheet.

Fig. 4 shows one manner in which selenium rectifiers of the kind shown in Fig. 3 may be assembled. Two rods 4 and 5 covered with insulating sleeves 6 and I respectively are used. Rectifiers la, lb, l'c, Id. are placed with the slots 2 embracing insulator 6 on rod 4 and are separated by means of metal spacers 8, 9, III, II, i2, covered by insulating sleeves l3, I4, I5, It. the metal sleeve l2 having no insulating sleeve covering. Rectifiers le, lg, If ih, are placed with slots 2 embracing insulator l on red 5 and are separated by means of metal spacers ll, l8, I9, 20, 2! covered by insulating sleeves 22, 23, 24, 25, the metal sleeve I! having no insulating sleeve covering.

The metal spacers are clamped between end plates 26, 21, threaded on both rods and insu-' lators d, 6, 6, 7, by means of insulating washers and nuts (not shown) so that there are two electrical circuits in parallel, one starting from end plate 28 and passing via metal spacer 8, low resistance direction of rectifier la, metal spacer 9, low resistance direction of rectifier lb, metal spacer it, high resistance direction of rectifier Ic, metal spacer ii, high resistance'direction of rectifier id, metal spacer l2, to end plate 21, and the other electrical circuit starting from end plate26 and passing via metal spacer ll, low resistance direction of rectifier ie, metal spacer l8, low resistance direction of rectifier If, metal spacer l9, high resistance direction of rectifier lg. m'etal spacer 20, high resistance direction of rectifier ih, metal spacer 2i to end plate 21.

The two electrical circuits are shown diagrammatically in Fig. 5. By inserting wiring tags be- Fig. 3 shows a rectangular disc I provided with tween the metal spacers and the rectifiers, c onnections as shown in Fig. 6 may be made. Any

other desired arrangement oi connections may be made by suitably arranging the number and direction oi assembly or the rectifiers and the wiring tag connections.

It is not always necessary that the end plates 24, 21 should be insulated from the rods 4. 5. In the particular case described above, insulating sleeves I and I may be shortened so that end plates 28, 21, both make contact with both'rods' 4 and I. The rods 4 and i then serve as the connection 28 in Fig. 6.

The slots 2 of rectifiers Ia, lb, 10, I d, fit against sleeves 22, 23, 24, 28, respectively and slots I of rectiflers le, I], I9, ih, fit against insulating sleeves l8, II, II, II, respectively.

An alternative form of rectifier disc which may be assembled similarly to the assembly of Fig. 4 is shown in Fig. 7 in which slots 2 and I are both large enough to embrace the insulating sleeve 8 or 1. In this case the mounting holes in the end plates 24, 21, through which the rods 4, 5, pass, may be elongated to enable the rods and rectiflers to be separated a short distance when it is neces-' longitudinal assembly member engaging one of the slots of the remaining discs, clamping means on said second member conductively interconnecting said remaining discs and holding the same in rigidly spaced relationship, means maintaining said two assembly members in spaced parallel relationship, and means for preventing the angular displacement of said discs, said last means including insulating means carried by each of said assembly members and engaging the other slot oi. each of the discs carried by the opposite member.

2. An assembly of dry contact rectifier discs comprising a series of discs each provided with two longitudinally aligned slots, one relatively shallow and the other relatively deep, a pair of assembly rods, means holding said rods in spaced parallel relationship, a plurality of conductive spacers insulatingly carried on the first rod and conductively interconnecting certain of said discs while holding the same in rigidly spaced relation- 4 ship along the rod, with slot thereoi'straddling said rod,- a plurality of conductive spacers insulatingly carried on the second rod and conductively interconnecting the remaining of said discs while holding the same in rigidly spaced relationship along said second rod, with the said relatively deep slot of said remainlng discs straddling said second rod, and a plurality of insulating spacers carried by each of said rods and engaging said relatively shallow slot of each disc held by the opposite rod whereby a the angular displacement of any oi said discs will be prevented.

8. An assembly of dry contact rectifier discs comprising a series of discs each provided with two longitudinally aligned slots, one relatively shallow and the otherv relatively deep. a pair of ,assembly rods, means holding said rods in spaced parallel relationship, an insulating sleeve surrounding each ot said rods, a plurality of metal spacers surrounding each of said sleeves and being each surrounded in turn by an individual tubaof insulating material, except for atmost one spacer on each rod. alternate discs being clamped between the said spacers on the first rod and the remaining discs being clamped between the said spacers on the second rod with the said relatively deep slot of each disc straddling the insulating sleeve 01 the respective rod to which it is clamped, and with the said relatively shallow slot of each disc engaging the periphery of a respective one of said insulating tubes carried by the opposite rod whereby the angular displacement of any of saiddiscs will be prevented.

ARTHUR MACKENZIE snsnnn REFERENCES CITED The following references are 01' record in the file of this patent:

UNITED STATES PATENTS Number the said relatively deep 

